Bae Du-na (left) stars as a blow-up sex doll who comes to life and gets a job at a video store working alongside Junichi (played by single-named actor Arata) in "Air Doll," the latest film by internationally-acclaimed director Hirokazu Kore-eda (Still Walking, After Life, Nobody Knows).

The idea is intriguing - an inflatable sex doll comes alive and experiences the world with wide-eyed innocence - but Hirokazu Kore-eda's "Air Doll" is only partly successful. The film's poignant depiction of human loneliness is undercut by saccharine notes and a drifting tone.

The setting is one of Tokyo's less fashionable neighborhoods, but we're really in the world of fairy tales and fables, appropriate for a Pinocchio story. A middle-aged waiter (Itsuji Itao) owns a life-size vinyl sex toy he calls Nozomi, who shares his dinner table (she doesn't talk much) and fulfills his sexual needs.

One day she stands up on her own ("I found myself with a heart," she says) and, when the waiter's away, begins to venture outside. Dressed in a French maid's outfit, Nozomi (Korean actress Bae Doona of "Sympathy for Mr. Vengeance") walks around town in mincing steps, and is delighted - everything's new to her.

She finds a job at a video store and slowly begins learning about life, from her co-workers, from the movies and from an old man sitting on a park bench. Perhaps inevitably, she falls in love with store's young clerk (Arata). Nozomi also encounters lonely neighbors with a variety of heartaches, including a young woman with an eating disorder, an older woman worried about her age and single dad and his daughter.

One day at the shop Nozomi cuts her hand and begins to deflate, which leads to unexpected consequences - but not before she travels to the inflatable-doll factory to meet her maker (Joe Odagiri).

Given the film's thematic content and Nozomi's innocence, it's possible to forget that she's a sex doll, but we're forcefully reminded of it from time to time.

As far as the acting goes, the film belongs to Bae and she's good if prone to overplay the whimsy.

Kore-eda ("Maborosi," "Still Walking") works in the humanist tradition, and while he peppers the film with some decent jokes, this is not an optimistic view of humanity. Whether this darkness sits well with the director's playful streak is open to debate. But there's no uncertainty about one thing: At 116 minutes, the film, based on a short manga by Yoshiie Goudais, is longer than it should be.